Fitting for flexible shaft casings



March 5, 1935. H. GoLDBERG FITTING FOR FLEXIBLE SHAFT CASINGS Filed June 22. 1951 Patented Mar. 5, 1935 i f. y i

YUNITED STATES PATENT OFFICE .1,393,368 FITTING Fon lFLEXIBLE SHAFT cAsINGs Herman Goldberg, chie-ego, In. y Application Jupe 2z, 1931, serial No. 5453393 -4 claims. (c1. (s4-3o) 4This invention relates to fittings for flexible accompanying drawing, in which one embodishaft casings and its purpose' is to provide an4 ment is illustrated. 4In the drawing, 'Y i improved fitting which will permit the convenient Fig. 1 shows a perspective View of a motor drive attachment of the ends of the casing tothe devices tool having the driving shaft thereof enclosed f5.' which operate or are operated by the flexible shaft in `a CaSing equipped With the improved 11171911185 -5 while at the same time permitting the universal of the present invention; Y movement of at leastone of these devices with. Fig. 2 shows a longitudinal verticalsection respectto the casing. Flexible-shafting is now through the fitting which SCInplOyed'a't the upper commonly employed for a, wide variety of uses end of the flexible shaft casing for connecting'it 10' and it is usual to drive one end of the shaft by With an extension 0f the Casing of the driving 10 an electric motor or the like and to connect the motor. other end of the shaft to a hand-manipulated de- Fig. 3 is a sectional view taken on the line 3 3 vice or tool, such as a Vpolishing implement, for f Fig. 2; and example, which is moved about by the operator Fig. 4 is a vertical longitudinal section similar l5l end whichmust assume a great variety of p osito that of Fig. 2, illustrating the formvof fitting 15 tions duringits operation. It is desirable to en- Which iS emDlOyCd' fOl` COIlneCting the lOWer 0r close this flexible shaft in a, flexible casing `haw free end of the fiexible shaft casing with the casing its endsconnected-tolthe casing of the manuing of the hand-Operated J0001 01" implementally operated implement and to the casing of the The apparatus illustrated in Fig'. 1 COInPI'iSCS driving motor, for example, and it has been found an electric motor 10 mounted with its shaft ex- 20 that the hard usage to which these sets of appatending vertically and having its casing pivotally ratus are put often results in the rapid deteriora- Connected at 11 t0' a hanger 12 Which may be tion `of the end portions of the casing and the provided at its upper end with a head 13 adaptsevering of their connections with the motor. or ed to. slide along a trolley and having contact I implement casings to which they are'ordinarily plates fOr making 0011115011011 With rSupply con- 25 connected. This has heretofore necessitated the dnCtOiS aSSOCiaiCd With the JGIOllCy S0 that the replacement'of the entire casing'with its end tmotor may bC'COnVeniCntlY InOVed about to vatings or the return of thedamaged casing to the rlous positions over a work bench, for examfactory for the repair of the end portions thereof, ple. vThe shaft of the motor extends downward- 30. thus necessitating great delay and expense and lythlOngha Casing extension 14 andthe lower 30 causing great loss to those whose tools are ren-A and 0f this Casing 14 iS COIineCed 130 a fitting 15 dered idle during this period, constructed according to the present invention.

The principal object of the present 'invention This itting 15 unites the Casing 14 With the flexiis to overcome the above mentioned difficulties hlBfShafi'f Casing 16 WliiCll COntainS the flexible by providing an improved form of fitting for flexi- Shaft having a connection with` the motor shaft 35 ble shaft casings which may be readily detached located in the casing 14. The flexible casing 16 by the workman in the shop and which may be is connected throughanother fitting 17, embodyreadily replaced byhim upon anew shaft casing. ing the present invention, with the casing 18 A further abject of the invention is toprovde an of a hand tool 19 which in this instance is illusimproved and simplified form of fitting for shaft Pwqted as a polishing deVCe-equpped'wth a D014 o casings which will permit a free universal movelshmg Wheel 20 driven bygthe flexible Shaft which ment of the manually operated implement which extends tilrqugh the casu,1g 1.6' The casing 13 is attached to the end of the casing and which of the pollshulg 17901 s ordmamy Supported upon may be' continued' in Operation for long periods alogkogfltgtl potauy Suspended from the of time without the development of looseness or r end play its parts- Anther object of the 1 The construction of the fitting 15 1s illustrated at'il'r'xa, Venfon 15.1"? Fronde an lmproved ttmg *for shaft ornlncrilsigyahnupoger 513351.53 lfn anlloswt'tsge Y a'smgs'havmg novel means by which the ttings 24through which extends the flexible shaft 2-5.

Clamp@ 0n the end 0f the casing other ObleCtS The lower end of the sleeve 23 isV enlarged and 50 relate tovvaricusfeatures of construction and alf-V has an externally knurled surface 23av while the y I rangement'whichwill appear more fully hereinlower sleeve 24 is enlargedat its upper end and after. y 9 l is s imilarlyprovided with an externally knurled The nature `of the invention will be understood surface 24a. These roughened surfaces permit the 55*l fromthe following specification takenA withthe partsto be engaged by the flngersof the work- 55 man so that they may be relatively rotated for the purpose of engaging or disengaging the two sleeves which have a telescoping threaded engagement with each other due to the provision on the sleeve 23 of an externally threaded extension 23b which telescopes within and threadedly engages the internally threaded enlarged portion 24b of the lower sleeve. The upper portion 23c of the upper sleeve is adapted to be clamped or otherwise secured to the casing 14 which extends downwardly .from the motor. The lower portion 231? of the upper sleeve and the lower portion of the sleeve 24 are adapted to receive the flexible shaft casing 16, the outer portion of which is ordinarily formed as a vulcanized tubular rubber body reenforced by strands of cord or fabric embedded therein and protected on its inner side by a metallic sheath within which the shaft 25 is mounted. The shaft casing 16 is extended `into the sleeves 23 and 24 and is held in position therein by anfannular splitring 26 having the form illustrated particularly in Fig. 3. `The lower end of the enlarged portion 24b of the lower sleeve 24 is yprovided with an annular downwardly and inwardly inclined wedging surface 24d and the split ring 26, engaging this surface,` is compressed and forced inwardly by the engagement therewith of thelower .end of the externally threaded projection 23,1? on the upper casing. This causes the split ring rto indent or bite into the rubber of the casing 16 so that this casing is then held firmly inA position within the fitting and is thus united rigidly at its upper end with the casing of the motor. In assembling the fitting on the upperend of the flexible shaft casing 16, the end of the casing is first inserted through the sleeve 24to project some distance above the upper end thereof and then, after .placing the split ring 26 imposition in the annular recess which is thus formed in the upper end of the sleeve 24 around the casing, the upper sleeve 23 is placed in position over the upper end of the casing and is then rotated to `cause its threaded portion 23b to engage the internally threaded portion 24:b of the lower casing. As the part 23b moves downwardly, the lower end'thereof engages the split ring 26 and forcesvit downwardly along the annular inclined wedging surface 24d with the result that the ring bites into the rubber casing and establishes a rigid connection therewith at the same timethat the two parts of the fitting are connected to each other.

The lower tting 17` is illustrated particularly in Fig. 4, where it is shown as comprising an upper sleeve 28 and a lower sleeve 29 together with other parts hereinafter to be described. The sleeves 22B/and 29 have'adjacent portions 28a and 29a which are externally knurled for engagement by the fingers of the operator and the part 283L is internally threaded for engagement by the externally threaded upper projection 29bv of the lower or outer sleeve. The upper sleeve 28 is provided at the upper end of the part 28*l thereof with an internal annular inclined surface 28d which is beveled upwardly and inwardly for coaction .with an annular split ring 30 which is similar in form to the ring shown in Fig. 3. As the lower surface 29 is threaded into the upper sleeve 28, the upper end of the extension29b engages the split ring 30 and forces it upwardly and v,inwardly along the wedging surface 28d so that it bites into the rubber of the casing 16 and thusholds theV casing firmly in position within the fitting. 1 This split ring in this fitting, as in the fitting first described, acts also as a locking device i,993,eee

to exert pressure on the contacting portions of the telescoping sleeves so that relative rotation thereof is not readily permitted. The sleeve 29 is provided at the lower end of the upper enlarged bore thereof with an annular shoulder 29f which may engage the lower end of the casing 16 and a similar shoulder is formed on one of the sleeves of the upper fitting 15 for the same purpose although this engagement is not essential since the resilient split rings 26 and SOeffectually resist any relative movement of the fittings with respect to the ends of the casing 16.

In order that the lower fitting 17 may allow the relative rotation of the casing 18 of the tool 19,

`this fitting 17 is provided with a relatively rotatable ltubular extension 32 which fits over the lower part 29c of the lower sleeve and which is freely rotatable thereon. The tubular extension 32 is internally threaded at its lower end as shown at 32a for engagement with a part carried by the casing'lS of thetool and the upper end of this extension 32 is provided with a plurality of annularly spaced circular holes 32b in each of which there is mounted a spherical hard metal ball 33. These balls Aare adapted to engage an annular groove 29d which is formed in the lower part 29c of the' lower sleevel Thisg'roove is substantially semicircular in cross-section to con-form to the curvature of the balls 33 and when these balls are in their inner positions engaging this groove, the extension 32 of the fitting is held in position on thesleeve 29 with its upper end engaging the annular shoulder 29 formed on the sleeve. The balls 33 are normally maintained in position to engage the groove 29d by a collar 34.- which ts over the tubular extension 32 with its upper end abutting againstpthe shoulder 29e and with its lower end engaged by a split resilient locking ring 35 which detachably engages an annular groove 32P? formed in the outer surface of the extension 32. This constructionpermits the ready' assembly or disassembly of the parts which lprovide the freely rotatable connection between the body of the fitting and the casing 18 of the tool and the toolA with the tubularextension 32 attached may be readily disconnected from the sleeve 29 when the operator wishes to place the sleeves 28 and 29 upon a new 16.

Although one form of the invention has been shown and described by way of illustration, it will be understood that it may be' constructed in various other embodiments within the scope of the appended claims'.

I claim:

1. The combination with a casing, of a flexible shaft in said casing, a fitting having parts extending over said casing and detachably. clamped thereon, said fitting comprising a projecting sleeve, a tubular extension fitting'over said sleeve and rotatable thereon, said tubular extension having an internally threaded portion for connection with va tool casing, and means for securing said tubular extension against endwise movement onsaid sleeve.

2. The combination with a shaft casing, of a fitting having parts extending over said casing and detachably clamped thereon, said fitting comprising a projectir'ig sleeve, ak tubular textension fitting over said sleeve land rotatable thereon, said tubular extensionA having an linternally threaded portion forconnection with a tool casing, said sleeve having an annular groove within said tubular extension, said tubular-extension having a plralityof 'apertures there' through, balls mounted in said apertures to engage said groove, and means for retaining said balls in engagement with said groove.

3. The combination with a shaft casing, of a ilexible shaft mounted in said casing and adapted to operate a tool, a fitting having parts extending over said casing and detachably clamped thereon, said fitting comprising a projecting sleeve, a tubular extension fitting over said sleeve and rotatable thereon, said tubular extension having an internally threaded portion for connection with a tool casing, said sleeve having an annular groove Within said tubular extension, said tubular extension having a plurality of apertures therethrough, balls mounted in said apertures to engage said groove, a collar fitting over said tubular extension to hold said balls in engagement with said groove, and means for detachably holding said collar in position on said tubular extension.

4. The combination in a tting for a. shaft casing, of a. projecting sleeve having an annular groove, a tubular extension rotatably mounted on said sleeve and having apertures therethrough, balls mounted in said apertures to engage said groove, a collar mounted on said tubular extension to retain said balls in said groove, said tubular extension having an annular groove at the end of said collar, and a resilient split ring engaging said last named groove.

HERMAN GOLDBERG. 

